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19
længere nedad delvis dækker dettes Sidefloie. Den nedre
Del er fortil afrundet, men bagtil uddraget i en skarp lige
nedadrettet Spids. Epimereme paa 2det Segment er
betydelig bredere og dækker en Del saavel af 1ste som 3die
Segment. De er i Enden bredt afrundede og her
bevæbnede med 2 tandformige Fremspring. 3die og 4de Segments
Epimerer er atter noget smalere og ligeledes ätandet. 5te
Segments Epimerer er noget bagudrettede og i Kanten
bevæbnede med 4 Tænder. Sidste Segment er betydelig
smalere end de øvrige og uden tydelige Epimerer. men nedentil
paa liver Side forsynet med en tydeligt markeret
Længde-kjol, der i Forbindelse med de 2 dorsale Kjoler giver dette
Segment et næsten qvadratisk Gjennemsnit. Dets bagre
Kant gaar oventil ud i 2 lange dolkformige Spidser, der
ligesom omfatter Roden af det midterste Halevedhæng, og
enhver af de ventrale Kjoler ender ligeledes med et
temmelig stærkt tandforinigt Fremspring.
Pan Bugsiden af de 5 forreste Segmenter findes
mellem Roden af Svommevedhængene en hoi sammentrykt Torn.
Øinene (Fig. 3 i er forholdsvis meget smaa, med korte
og tykke Stilke. Den facetterede Del. der viser et mørkt,
brunsort Pigment, er ikke som sædvanlig fortykket, men
tvertimod af ringere Diameter end selve Øienstilken ved
Roden. Den dækkes oventil for en Del af en tilspidset
med nogle korte Børster besat Fortsats.
1ste Par Folere iFig. 4) er kun lidet udviklede,
neppe mere end halvt saa lange som Bygskjoldet, og
bestaar som sædvanlig af et 31eddet Skaft og 2 mangeleddede
Svøber. Skaftets 1ste Led er næsten dobbelt saa langt
som de 2 øvrige tilsammen og gaar ved Boden paa den
ydre Side ud i en bred. næsten hjerteformig Fortsats. der
er udtrukket i en skarp, noget udadbøiet Spids.
Fortsatsen omslutter, som hos andre ilamirer, en temmelig
rummelig Hule (Horecavitet), som aabner sig udad med en
trang spaltformig Aabning paa den nedre Side; den er i
Kanterne fint cilieret og desuden paa den øvre Side nær
den ydre Band forsynet med 5—(i lange sabelformige Torner.
Den ydre Del af Leddet er cylindrisk og i begge Kanter,
men især den indre, tæt besat med tynde, fint eilerede
Borster. Paa den nedre Side findes nær den indre Kant
og omtrent i Midten af Leddets Længde et lidet fortilrettet
tornformigt Fremspring, hvorfra en Kjøl strækker sig bagtil.
Skaftets sidste Led er ganske kort. neppe mere end halvt
saa langt som 2det og i Enden skraat afskaaret; begge
Led i Kanterne borstebesatte.
Svøberne forholder sig noget ulige hos begge Kjon.
Hos Hunnerne (Fig. 4) er de neppe længere end Skaftet
og indbyrdes omtrent af ens Længde. Den ydre Svobe.
der ved et meget bevægeligt, kort og tykt. næsten skaal-
carapax. whereas, farther down, they partially overlap the
lateral lobes of that part. The lower division is rounded
anteriorly, but posteriorly produced into a sharp point
directed straight downward. The epimera on the 2nd
segment are considerably broader and partially overlap both
the 1st and 3rd segments. At the extremity they are broadly
rounded, exhibiting here 2 dentiform projections. The epimera
of the 3rd and 4th segments are again much narrower and.
also bidentate. The epimera of the 5th segment are
somewhat posteriorly directed and furnished along the margin
with 4 teeth. The last segment is much more slender than
the others and without any true epimera, but below, on each
side, provided with a distinctly marked longitudinal carina,
which, in conjunction with the 2 dorsal carinæ. gives to
the transverse section of this segment an almost quadrate
appearance. Its posterior margin projects above with 2
long dagger-shaped points, that embrace, as it were, the
base of the telson, and each of the ventral carinæ
terminates likewise in a comparatively strong dentiform
projection.
On the ventral surface of the 5 anterior segments,
occurs between the bases of the pleopods a high, compressed
spine.
The eyes (fig. 3) are comparatively very small, with
short and thick pedicles. The cornea, which exhibits a dark,
brownish-black pigment, is not, as commonly the case,
dilated, but. on the other hand, smaller in diameter than the
pedicle of the eye itself at the root. It is covered above,
partially, by an acutely pointed projection, beset with short
bristles.
The 1st pair of antennæ (fig. 4) are but
slightly-developed. being scarcely more than half as long as the
carapax. and consist as usual of a triarticulate peduncle
and 2 multi-articulate flagella. The lst joint of the peduncle
attains almost twice the length of the other 2 taken together,
and at the outer side is seen projecting from its base a
broad, almost cordiform process, which is produced into a
sharp, somewhat outwardly bent point. The projection
encloses, as in other Macrura, a rather spacious chamber
(auditory cavity), which opens exteriorly with a narrow,
fissure-shaped orifice on the lower side; along the margins
it is finely ciliated, and on the upper side, in proximity
to the outer margin, furnished besides with 5 or 6 ensiform
spines. The terminal portion of the joint is cylindrical,
and on both sides, but more especially the inner, closely
beset with slender, finely ciliated bristles. On the lower
side, near the inner margin, and about in the middle of
the longitudinal diameter of the segment, occurs a small,
anteriorly directed, spiniform projection, from which a short
keel extends posteriorly. The last joint of the peduncle
is very short, scarcely more than half the length of the
2nd. and the extremity obliquely truncate: both
articulations furnished with bristles along the margins.
The flagella are somewhat different in the two sexes.
The females (fig. 4) have them scarcely longer thai) the
peduncle and well-nigh uniform in length. The outer
flag-ellum. connected with the peduncle by an extremely mobile,
3*
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